Flux-cored Wire Electrode for Ar+CO Gas Shielded Arc ...
Transcript of Flux-cored Wire Electrode for Ar+CO Gas Shielded Arc ...
DOC.No.072003-U047 Jun.2003
Flux-cored Wire Electrode for Ar+CO2 Gas Shielded Arc Welding
"DWA-81Ni1"
Productivity through filler metal selection exocor.com
1
Doc.No.072003-U047
Flux-cored Wire Electrode for Ar+CO2 Gas Shielded Arc Welding
"DWA-81Ni1"
AWS A5.29-1998 E81T1-Ni1MJ
EN 758-1997 T46 6 1Ni P M 2 H5
1. Description
DWA-81Ni1 is an easy-to-use, titania based flux-cored wire electrode for all
positional single pass and multiple-pass welding of mild steel to 550N/mm2 class
high strength steel with Ar+CO2 shielding gas. This wire is applicable to low
temperature service steel being used at down to -60℃.
DWA-81Ni1 wire electrode has a lot of characteristics as follows :
1) High notch toughness of welds at low temperature down to -60℃ with as welded
condition and to -40℃ after PWHT(580℃×1hr/inch).
2) Excellent weldability can be obtained in all position.
3) All positional welding can be achieved with good bead appearance, negligible
spatter losses, and easy slag removal.
2. Properties of all-weld metal
Mechanical properties and chemical composition of all-weld metal with DWA-81Ni1
are shown in Tables 2, 3 and Figure 1.
Table 2 Mechanical properties of all-weld metal
0.2% PS
N/mm2
TS
N/mm2
El%
RA%
vE-80℃ vE-60℃ vE-40℃
61 (60) 162 (13) 161 (18) 43 (65) 116 (20) 140 (10) 19 (71) 147 (15) 156 (16)
Avg. 41 (65) Avg.142 (16) Avg.153 (15)145 (31) 135 (26)109 (20) 142 (17)133 (34) 141 (25)
Avg.128 (34) Avg.139 (23)
―SR
517 582 29
PWHTTensile properties Absorbed energy, J
AW 71
7130578490
According to AWS A5.29
280Amp.-29~30Volts, 14passes-7layers, 80%Ar+20%CO2(25 l/min)
PWHT condition : SR, 580℃×2hr. Heating and cooling rate:50℃/hr
Values in parentheses show the percent brittle fracture.
Productivity through filler metal selection exocor.com
2
Table 3 Chemical composition of all-weld metal (%)
C Si Mn P S Ni Ti B
0.049 0.32 1.26 0.006 0.006 0.95 0.041 0.0052
0
20
40
60
80
100
-90 -80 -70 -60 -50 -40 -30
Brittle fracture (%)
0
20
40
60
80
100
120
140
160
180
-90 -80 -70 -60 -50 -40 -30
Temperature (℃)
Absorbed energy (J)
――○―― AW― ―●― ― SR
――○―― AW― ―●― ― SR
Fig.1 Transition curve of all-weld metal
3. Diffusible hydrogen content in weld metal
Table 4 Diffusible hydrogen content in deposited metal (ml/100g) 1 2 3 4 Average
4.1
4.0 4.4 4.9 4.4
*1 Welding conditions : 280A-29V-30cm/min., Wire extension=25mm
Productivity through filler metal selection exocor.com
3
4. Butt weld test result
(1) Test conditions
Testing conditions are shown in Table 5.
Table 5 Test conditions Items Details
Steel plate
FH36, Plate thickness=50mm
50t×(250+250)w×850l mm ,
2 plates in each welding position
Double bevel groove
1st side : Groove angle=50°, Groove depth=33mm
2nd side : Groove angle=60° Groove depth=15mm
Root face : 2mm
* After welding 1st side, the groove
of 2nd side was machined to the
shape of 50° groove angle, 28mm groove depth.
Groove shape
33
2
15
50
28
R=5
50°
60°
50°
[Unit:mm]
<1st>
<2nd>
Welding procedure Manual welding
Welding position Horizontal(PC) and Vertical upward(PF)
Welding parameters Horizontal(PC) : 260Amp., 28Volts
Vertical(PF) : 220Amp., 25Volts
Pass sequence
Horizontal(PC) : 1st side = 36passes-8layers
2nd side = 39passes-6layers
Vertical(PF) : 1st side = 18passes-7layers
2nd side = 13passes-6layers
Heat input Horizontal(PC) : 0.92kJ/mm
Vertical(PF) : 1.86kJ/mm
Shielding gas 80%Ar+20%CO2, 25 l/min
Preheating temperature 100℃
Interpass temperature 100~150℃
PWHT
As welded,
SR treatment
Heating rate: 104~108℃/hr
Holding temp. & time: 579~581℃, 2~2.2hrs,
Cooling rate: 68~ 75℃/hr
Controlled lower limit temp.: 80℃
Productivity through filler metal selection exocor.com
4
(2) Test results
Macrostructures of welded joints are shown in Photo 1. Results of tensile test
and impact test are shown in Table 6, Figures 2 and 3. CTOD test results are shown
in Table 7. Chemical compositions of weld metals are shown in Table 8.
(a) Horizontal position (PC)
(b) Vertical position (PF)
Photo 1 Macrostructures of welded joints
Productivity through filler metal selection exocor.com
5
Table 6 Mechanical properties of welded joints
vE-60℃ vE-50℃ vE-40℃
1st 592 628 25 71
91 (13) 84 (24) 87 (18)
Avg. 88 (18)
118 (11) 95 (14)105 (13)
Avg.106 (13)
133 ( 3)106 ( 7)115 ( 7)
Avg.118 (6)
<-60
Center - - - -
53 (38) 63 (11) 66 (24)
Avg. 61 (24)
89 ( 6) 82 (43) 82 (21)
Avg. 84 (23)
89 ( 8)110 (13)100 (15)
Avg.100 (12)
<-60
2nd 581 604 25 68
56 (43) 66 (46) 43 (60)
Avg. 55 (50)
105 (14)129 ( 2) 90 (20)
Avg.108 (12)
103 (13) 90 (23)123 ( 0)
Avg.105 (12)
-60
1st 583 647 25 62
21 (61) 16 (70) 18 (60)
Avg. 18 (64)
42 (60) 40 (55) 28 (45)
Avg. 37 (52)
42 (46) 57 (40) 52 (39)
Avg. 51 (42)
-48
Center - - - -
46 (57) 43 (63) 44 (43)
Avg. 44 (54)
68 (34) 49 (38) 71 (46)
Avg. 63 (39)
81 (24) 77 (28) 75 (23)
Avg. 78 (25)
-57
2nd 533 596 26 63
25 (69) 63 (45) 37 (46)
Avg. 42 (53)
66 (47) 45 (59) 42 (47)
Avg. 51 (51)
70 (35)125 (14) 64 (41)
Avg. 87 (30)
-50
1st 530 586 28 71
49 (34) 82 (29) 72 (31)
Avg. 67 (31)
92 (21) 96 (22) 93 (27)
Avg. 94 (23)
88 (16) 99 (21) 91 (25)
Avg. 93 (21)
<-60
Center - - - -
96 (12) 85 (11)100 (17)
Avg. 94 (13)
110 (11)100 (13)107 (11)
Avg.105 (12)
127 ( 4)129 ( 1)117 ( 9)
Avg.124 (5)
<-60
2nd 544 604 27 71
111 (12) 94 (15) 81 (24)
Avg. 95 (17)
130 (12)115 (13)121 ( 4)
Avg.122 (10)
128 ( 6)129 ( 7)139 ( 7)
Avg.132 ( 7)
<-60
1st 525 595 26 70
63 (62) 50 (61) 33 (65)
Avg. 49 (63)
78 (43)100 (29) 80 (45)
Avg. 86 (39)
107 (31)110 (23)110 (28)
Avg.109 (27)
-53
Center - - - -
23 (65) 38 (56) 46 (61)
Avg. 36 (61)
53 (44) 41 (56) 37 (58)
Avg. 44 (53)
63 (34) 55 (54) 69 (32)
Avg. 62 (40)
-47
2nd 509 591 30 71
68 (45) 67 (39) 76 (39)
Avg. 70 (41)
96 (35)113 (28) 63 (44)
Avg. 91 (36)
136 (18)137 (15)106 (21)
Avg.126 (18)
<-60
Weldingposition
Vertical(PF)
Heat input1.86kJ/mm
PWHTvTrs(℃)
Horizontal(PC)
Heat input0.92kJ/mm
AW
SR
AW
SR
Absorbed energy, JSide
TS
N/mm2
El%
RA%
0.2% PS
N/mm2
Values in parentheses show percent brittle fracture.
PWHT condition : SR, Holding temp. and time : 579~581℃, 2~2.2hrs
Heating rate : 104~108℃/hr
Cooling rate : 68~ 75℃/hr
Locations of specimens:
1st, 2nd = 7mm from the face of the test plates, each.
Center = Center of the plate thickness.
Productivity through filler metal selection exocor.com
6
0
20
40
60
80
100
-70 -60 -50 -40 -30
Brittle
fracture
(%)
0
20
40
60
80
100
120
140
160
-70 -60 -50 -40 -30
Temperature (℃)
Absorbed
energy (
J)
― ―●― ― 1st - - △ - - Center ――○―― 2nd
― ―●― ― 1st - - △ - - Center ――○―― 2nd
0
20
40
60
80
100
-70 -60 -50 -40 -30
Brittle
fracture
(%)
0
20
40
60
80
100
120
140
160
-70 -60 -50 -40 -30
Temperature (℃)
Absorbed
energy (
J)
― ―●― ― 1st - - △ - - Center ――○―― 2nd
― ―●― ― 1st - - △ - - Center ――○―― 2nd
(a) As welded (b) PWHT (580℃×2hrs)
Fig.2 Transition curves of weld metals in horizontal position(PC)
0
20
40
60
80
100
-70 -60 -50 -40 -30Bri
ttle frac
ture (%)
0
20
40
60
80
100
120
140
160
-70 -60 -50 -40 -30
Temperature (℃)
Absorbed
energy
(J)
― ―●― ― 1st - - △ - - Center ――○―― 2nd
― ―●― ― 1st - - △ - - Center ――○―― 2nd
0
20
40
60
80
100
-70 -60 -50 -40 -30Brittl
e fractur
e (%)
0
20
40
60
80
100
120
140
160
-70 -60 -50 -40 -30
Temperature (℃)
Absorbed
energy
(J)
― ―●― ― 1st - - △ - - Center ――○―― 2nd
― ―●― ― 1st - - △ - - Center ――○―― 2nd
(a) As welded (b) PWHT (580℃×2hrs)
Fig.3 Transition curves of weld metals in vertical position(PF)
Productivity through filler metal selection exocor.com
7
Table 7 CTOD test results (as welded)*1,2
50.31 100.10 51.18 600 212.5 1.11 6(δm) 0.3850.46 100.10 51.07 600 222.5 1.11 6(δm) 0.3850.38 100.08 50.98 600 221.0 1.10 6(δm) 0.3850.24 100.09 50.86 550 224.5 2.04 6(δm) 0.6550.35 100.10 50.96 550 231.5 2.43 6(δm) 0.7650.32 100.10 50.75 550 229.0 2.48 6(δm) 0.77
*1 According to BS7448-1991 *2 Precompression : 33mmφ, 900kN, 30sec, Actual strain : 0.30~0.48% *3 The value in parentheses shows CTOD when pop-in is ignored.
CriticalCTOD(mm)
Horizontal(PC)
Vertical(PF)
-10
-10
WeldingPosition
Test Temp.(℃)
B
(mm)
W
(mm)
CrackLength
a(mm)
YieldStrength
σy
(N/mm2)
AppliedForceFc,u,m(kN)
Vc,u,m
(mm)
Type ofF-V
Table 8 Chemical compositions of weld metals*1 (mass%) Weldingposition
Side C Si Mn P S Ni Ti B
1st 0.048 0.31 1.27 0.007 0.007 0.96 0.052 0.0050
Center 0.049 0.31 1.28 0.007 0.007 0.98 0.049 0.0051
2nd 0.049 0.31 1.25 0.008 0.008 0.98 0.053 0.0050
1st 0.043 0.29 1.20 0.006 0.005 0.99 0.037 0.0051
Center 0.050 0.30 1.28 0.007 0.006 0.90 0.044 0.0056
2nd 0.049 0.31 1.25 0.008 0.007 0.96 0.046 0.0057
0.07 0.18 1.44 0.006 0.001
*1 Locations of analysis : The same locations as the impact tests.*2 Ceq.=C+Mn/6+(Cu+Ni)/15+(Cr+Mo+V)/5 PCM =C+Si/30+(Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+B*5
Ceq.=0.32*2
PCM =0.16*2
Vertical(PF)
Heat input1.86kJ/mm
Horizontal(PC)
Heat input0.92kJ/mm
Base metal(FH36)
5. Shipping approvals
Shipping approvals are shown in Table 9.
Table 9 Shipping approvals Classification
society LR ABS DNV
Grade 5Y42 5YQ420
4Y400(MG)
ⅤY42
ⅤY
Productivity through filler metal selection exocor.com
8
Appendices
A-1. Welding conditions
Details of the welding conditions are shown Tables A-1 and A-2.
Table A-1 Welding conditions in horizontal position(PC)
1 1 260 28 38.6 1.13 106 1 1 260 28 40.2 1.09 1212 2 260 28 53.1 0.82 132 1 2 260 28 44.3 0.98 1222 3 260 28 43.2 1.01 134 2 3 260 28 49.0 0.89 1313 4 260 28 56.7 0.77 127 2 4 260 28 36.4 1.20 1213 5 260 28 47.7 0.92 136 2 5 260 28 41.5 1.05 1323 6 260 28 48.1 0.91 135 3 6 260 28 42.9 1.02 1264 7 260 28 56.0 0.78 124 3 7 260 28 50.5 0.87 1324 8 260 28 54.3 0.81 132 3 8 260 28 36.7 1.19 1334 9 260 28 54.3 0.81 135 3 9 260 28 43.6 1.00 1354 10 260 28 50.0 0.87 130 3 10 260 28 50.5 0.87 1325 11 260 28 51.0 0.86 145 4 11 260 28 51.0 0.86 1295 12 260 28 54.8 0.80 141 4 12 260 28 48.1 0.91 1295 13 260 28 52.0 0.84 145 4 13 260 28 46.4 0.94 1285 14 260 28 56.0 0.78 144 4 14 260 28 47.7 0.92 1255 15 260 28 47.2 0.92 138 4 15 260 28 36.4 1.20 1296 16 260 28 55.4 0.79 139 4 16 260 28 42.9 1.02 1286 17 260 28 56.0 0.78 141 4 17 260 28 48.1 0.91 1296 18 260 28 54.3 0.81 137 5 18 260 28 50.5 0.87 1266 19 260 28 51.5 0.85 138 5 19 260 28 49.0 0.89 1306 20 260 28 52.0 0.84 136 5 20 260 28 47.2 0.92 1256 21 260 28 45.1 0.97 133 5 21 260 28 47.2 0.92 1257 22 260 28 49.0 0.89 143 5 22 260 28 44.0 0.99 1267 23 260 28 48.6 0.90 147 5 23 260 28 44.7 0.98 1307 24 260 28 50.5 0.87 145 5 24 260 28 48.1 0.91 1247 25 260 28 47.2 0.92 143 5 25 260 28 44.0 0.99 1257 26 260 28 50.5 0.87 143 5 26 260 28 42.5 1.03 1297 27 260 28 49.0 0.89 142 5 27 260 28 42.5 1.03 1277 28 260 28 45.1 0.97 142 5 28 260 28 50.0 0.87 1288 29 260 28 46.4 0.94 130 6 29 260 28 47.7 0.92 1278 30 260 28 44.7 0.98 136 6 30 260 28 49.5 0.88 1238 31 260 28 45.1 0.97 138 6 31 260 28 50.5 0.87 1308 32 260 28 46.8 0.93 136 6 32 260 28 49.5 0.88 1288 33 260 28 47.7 0.92 138 6 33 260 28 48.1 0.91 1288 34 260 28 47.2 0.92 137 6 34 260 28 50.5 0.87 1278 35 260 28 43.2 1.01 131 6 35 260 28 51.0 0.86 1268 36 260 28 50.0 0.87 138 6 36 260 28 52.0 0.84 127
6 37 260 28 51.0 0.86 1256 38 260 28 43.6 1.00 1226 39 260 28 59.3 0.74 126
Avg. 0.89 Avg. 0.95Average of both side 0.92
InterpassTemp.(℃)
2nd
WeldingCurrent(Amp.)
ArcVoltage(Volt)
WeldingSpeed
(cm/min)
HeatInput
(kJ/mm)
1st
Side Layer PassArc
Voltage(Volt)
WeldingSpeed
(cm/min)
HeatInput(kJ/mm)
InterpassTemp.(℃)
Side Layer PassWeldingCurrent(Amp.)
Table A-2 Welding conditions in vertical position(PF)
1 1 220 25 15.0 2.20 104 1 1 220 25 17.9 1.84 982 2 220 25 16.6 1.99 126 2 2 220 25 15.9 2.08 1163 3 220 25 19.6 1.68 144 3 3 220 25 25.8 1.28 1293 4 220 25 14.3 2.31 123 3 4 220 25 17.2 1.92 1254 5 220 25 16.5 2.00 133 4 5 220 25 18.5 1.79 1314 6 220 25 21.3 1.55 133 4 6 220 25 15.8 2.09 1354 7 220 25 13.7 2.41 112 5 7 220 25 16.8 1.96 1205 8 220 25 16.3 2.03 138 5 8 220 25 18.7 1.77 1305 9 220 25 17.3 1.91 129 5 9 220 25 13.7 2.41 1305 10 220 25 17.4 1.90 134 6 10 220 25 17.8 1.86 1336 11 220 25 18.2 1.81 131 6 11 220 25 17.4 1.90 1386 12 220 25 19.0 1.73 138 6 12 220 25 20.7 1.59 1396 13 220 25 24.6 1.34 146 6 13 220 25 18.0 1.83 1356 14 220 25 23.4 1.41 1367 15 220 25 17.3 1.90 1347 16 220 25 18.3 1.81 1367 17 220 25 20.7 1.59 1347 18 220 25 19.4 1.70 133
Avg. 1.85 Avg. 1.87Average of both side 1.86
Side Layer PassWeldingCurrent
ArcVoltage
WeldingSpeed
HeatInput
InterpassTemp.
Side Layer PassWeldingCurrent
ArcVoltage
WeldingSpeed
HeatInput
InterpassTemp.
1st 2nd
Productivity through filler metal selection exocor.com
9
A-2. Microstructures of weld metal 1st side 2nd side
As welded SR (580℃×2hrs) As welded SR (580℃×2hrs)
As
casted
zone
(X100)
As
casted
zone
(X400)
Refin-
ed
zone
(X400)
Photo A-1 Microstructure of weld metal in horizontal position(PC)
100μm
25μm
25μm
Productivity through filler metal selection exocor.com
10
1st side 2nd side
As welded SR (580℃×2hrs) As welded SR (580℃×2hrs)
As
casted
zone
(X100)
As
casted
zone
(X400)
Refin-
ed
zone
(X400)
Photo A-2 Microstructure of weld metal in vertical position(PF)
100μm
25μm
25μm
Productivity through filler metal selection exocor.com
11
A-3. Load-displacement records in CTOD tests
Horizontal position (PC)
Vertical position (PF)
Scale
Fig. A-1 Load-displacement records in CTOD tests
Productivity through filler metal selection exocor.com
12
Welding
position 1 2 3
Horizontal
(PC)
Vertical
(PF)
Photo A-3 Appearance of fracture surface of CTOD test specimens
Productivity through filler metal selection exocor.com